Take a look at this game. How can someone tell me that Gemstone didn't inspire it? They even have a more difficult area on the game called "The Rift", where you can get extra special weapons and treasure: http://youtube.com/watch?v=g3A_m9RDzL8&t=82s

You know that essentially every fantasy setting since the 1940s has had orcs, elves, etc., regardless of medium (text, video, game [PC or console]), right?
(I will grant that it is not a 100% match, but... yeah, they [nearly] all have 'em.)

Gonna have to agree with Krakii's detail post on why it isn't and with Kandor's awesomely short and to the point rolton post. Also the whole Rift concept isn't unique to Simutronics and Gemstone either and has been used and mentioned in fantasy, science fiction books as well as tabletop rpgs.